Safety device.



C. F. ROOT.

SAFETY DEVICE.

. APPLICATION FILED ocT.5.1914.

Patented Mar. 25, 1919.

3 SHEETS-SHEET l.

C. F. ROOT.

SAFETY DEVICE.

APPLICATION FILED OCT. 5,1914

1,298,567. Patented Mm. 25,1919.

3 SHEETS-SHEET 3.

PATENT FFICE,

CHARLES E. ROOT, OF RAVENNA, OHIO, ASSIGNOR OF ONE-FOURTH T0 BYRON O.CONN, OF MANSFIELD, OHIO.

SAFETY DEVICE.

Specication of Letters Patent.

Patented Mar. 25, 1919.

To all whom z't may concern:

lie it known that I, CHARLES F. ROOT, a citizen of the United States ofAmerica, residing at Ravenna, in the county of Portage and State ofOhio, have invented certain new and useful Improvements in SafetyDevices, of which the following is a specification.

This invention relates to certain new and useful improvements in safetydevices foi staying machines, though equally applicable to any characteror type of machine which has a reciprocating work engaging element, asfor example a punching press.

The object of my invention is to provide means for automaticallypreventing the link that imparts movement to the reciprocating workengaging element from operating when an obstruction is inadvertently orotherwise placed between the element and the anvil and upon engagementof the element with the obstruction.

It is well known in the operation of machines that are provided with areciprocating work engaging element which exerts a pressure upon ananvil, die or vthe like, that there is great danger of the operatorsfingers being inadvertently placed between the anvil or die and thereciprocating element that exerts pressure to perform the work. with theresult that the fingers are crushed or injured.

rlhis is especially true when it is necessary for the operator of themachine to perform work that requires him to place his hands in closeproximity to the anvil or die of the machine, and in manipulating thework his hand is liable to be engaged by the reciprocating workingelement at the time the latter is about to perform its work.

The primary object, therefore, of my invention is to provide means ofrelieving the pressure. that is exerted by the reciprocating elementupon the anvil or die to perform the work when an obstruction isinterposed between the anvil or die and the reciprocating element.

rlhe primary object of the invent-ion is to provide a machine of thetype set forth with mechanical means embodiedin the reciprocatingelement, which automatically causes the element to remaininoperative,'if in its descent any obstruction, such as the hand of theoperator, or one of the fingers of the hand, is met with.

Further, the invention aims to provide means which is incorpo lated inthe reciprocating element so as to only render the latter opent-ire, orrigid, just prior to or at the instant of commencement of the punching,pressing, forming or stamping operation, or in other words, only at theinstant that the reciprocating element is about to enter into actual orphysical contact with the work.

Still further, the invention aims to provide means which is sensitive tooperation by the linger or hand of the operator, should the finger orhand be in a position subject to injury by the reciprocal element,without actual injury to the finger or hand.

Furtheigthe invention aims to provide a structure which can be adjustedto operate in connection with material possessed of varying thicknesses.

The objects above described are set forth in. Letters Patent granted toine bearing date of March 9, 1915, Patentv Number 1,131,161 and pendingapplication bearing Serial No. 857,016, filed August 17, 1914, and thepresent application has the same objects in view in generalbut includesimprovements in the structure described in said applications andconsists in the followinonew features, to wit:

I@am actuated means to positively render the reciprocating elementinoperative until it reaches a predetermined point in its working strokeand means to render said reciprocating element operative at saidpredetermined point or just prior to said element acting upon the work.

A .further object is to provide a safety device for connecting thereciprocating element with its actuating means that is self containedand that can be applied without making any changes or alterations inmachines already in use which are provided with reciprocating workingelements such as punching presses, printing presses, staying machinesand the like.

Another object is to provide a safety device for actuating` thereciprocating element of the class of machines described that will berendered inoperative, until it reaches a predetermined point in itsworkingv stroke, to exert a pressure upon any obstruction eX- traneousto or interposed between said reciprocating working element and the workupon which it acts although a part or parts of the mechanism be out ofrepair, disarranged, or broken.

A further object is to construct a: simple and effective safety devicecomposed of minimum parts.

The essential feature of the invention comprises a link having a slot, ahalf link slidable in the slot, a disk having an actuating cam formedthereon, a pivoted locking bar to lock the link and half link, and meansto move the bar to locking position when disengaged from the cam, thelatter acting to normally hold the bar out of locking position.

A further object is to -so construct, combine and arrange the mechanismof a safety actuating means for imparting a reciprocating movement tothe work engaging element of a machine, that the friction of the partsvin operation and their liability to become deranged will be reduced to aminimum so that a slight resistance or pressure exerted upon the workengaging element by a finger or other Lobstruction extraneous to thework will render the work engaging element inoperative to exert workingpressure.

Another object is to provide devices which will give the very leastamount of pressure on a ingeror other obstruction extraneous to the workby reducing the friction of the parts to a minimum, also reducing to aminimum the chance of said parts becoming wedged.

I attain these and other objects by the mechanism illustrated in theaccompanying drawings, in which:

Figure 1 is a frontelevation of a conventional ytype of staying machineshowing the invention applied thereto and also showing the finger of theoperator interposed between the anvil (which has a paper box mountedthereon) and the reciprocating work engaging element;

Fig. 2 is a detail view, in rear elevation of the link. half link andlocking bar, looking from the rear toward the front of the stayingmachine, showing the half link interlocked with the link by a pivotallocking vbar in dotted lines and unlocked therefrom in full lines.

Fig. 3 is a side view partly in section showing the l1nk,half link andlocking bar,

and cam disk assembled, mounted upon `a bushing and connected to thedisk and crank pin of the driving shaft.

Fig. 4 is a side elevation partly in section of Fig. 1 on a reducedscale.

F ig. 5 is a front elevation of a cam diskl showing a cam formedthereon.

Fig. 6 is a side elevation of Fig. 5.

In the drawings, the driving shaft 1 is provided with a disk 2 having acrank pin 3, the shaft being journaled in suitable bearings in theL-shaped arm 4 of a conventional type of a staying machine. Movement isimparted to the driving shaft 1 by the driving pulley 5. A head 6reciprocates between the ways 7 and has a stud shaft `8 secured thereto.A. follower or work engagingk element 9 is securely attached to the head6 and cooperates with the usual anvil 10 of staying machine or the like.

For the purpose of connecting the stud shaft 8 of the head to the lcrankpin 3 of the driving shaft l, by means of which reciprocating movementis imparted to the head 6, link 11, which is adapted to be interlockedwith and released from a half link 12 by the pivoted locking bar 13, isprovided. The link 11 is cut away or reduced on one side thereof at 14,forming a shoulder or abutment 15, which is adapted to Contact with thefree lower end 16 of the locking bar and o-set portion 17 thereof.

A bearing or bushing 18 is secured to thev upper end of the half link 12and has one end thereof slidably projecting into han oblong slot 19which is formed in the upper part 2O of the link 11. The bushing 18 issecurely fastened to the half link 12 by pin 21 and supports the link 11and half` link 12 and in turn is loosely mounted upon the crank pin 3.The bushing 18 is also provided on one end with an annular flange 22which fits into the counter-bored portion 23 of a disk 24.

The function of the above parts will be described more specificallyhereinafter.

An aperture 25 is formed in one end of the link 11 to provide a bearingfor the,

stud shaft 8 of the head 6. The locking bar 13 is pivoted to the halflink 12 by the stud pin 26. A finger 27 is formed on the upper end ofthe locking bar.

In assembling, applying and constructing my safety device, the disk 24is counterbored on one side, as shown at 28, to fit over the disk 2which is carried by the driving shaft 1, the crank pin 3 passing throughan aperture 29 provided in the disk. Acam 30 is provided on one side o-fthe disk 24.

In connecting and applying the device to a staying machine or the like,the bushing 18 is loosely fitted in the aperture 29 in the disk 24 so asto permit the disk to rotate upon, the bushing, the annular flange 22of` A4'the bushing seatingin the counter-bore 23 with the face 31 of thebushing flush with the face 31 of the counter-bore. The half link isthen mounted upon and secured to the bushing and the projecting end 32of the bushing passed through the slot 19 of the link 11 therebyproviding means for supporting and carrying said link.

The tang 33 of the lhalf link is iitte'd to slide between the guides 34and 35. The locking bar 13 is pivotally mounted upon the half link byinserting the stud pin 26 in a suitable aperture formed in the tangportion 33 of the half link.

The locking bar is maintained in its proper place against lateralmovement by its finger 27 which projects into a space (provided by thewidth of the cam) between the disk 24 and the upper portion of the halflink.

he operation of my device is as follows: vWhen movement is imparted tothe driving shaft, the crank pin 3 imparts a combined oscillating` andreciprocating movement to the link and the half link which supports thelocking bar and at the same time imparts a rotary movement to the camdisk 24 upon which is formed the cam 30 and as the disk is rotated thecam between the points 36 and 37 thereof contacts with the linger 27 ofthe locking bar positively forcing it to pivot upon the stud pin 26thereby releasing the end 16 from its position in contact with theabutment 15 as ,shown in Fig. 2 in full lines, and maintaining thelocking bar in said released position until the cut away portion 38 ofthe cam is alined with the nger 27 at which time the locking bar ispermitted to pivot upon the stud pin to the locked or dotted lineposition shown in Fig. 2.

The spring 39 contacts with and normally exerts a pressure against thelower end of the locking bar to force the end 16 and `off-set 17 incontact with the abutment 15 and end of the half link, or in lockedposition. After the crank pin has traveled to a predetermined pointwhich is preferably to within of an inch of the end of its workingstroke, the end 16 of the locking bar 13 is forced by spring 39 toengage with the abutment or shoulder 15 and the olf-set 17 with theabutment 15 and the end 40 of the half link 12 (as shown in dotted linesin Figs. 2 and 3.).

Theface of the cam 30 is so arranged that when the crank pin is on itsrip-stroke and has traveled to a point within 2,- of an inch of the endof its down-stroke carrying the link, half link, and locking bar, thecam will be in contact with the finger 27 forcing the end 16 of thelocking bar in unlocked position as shown in full lines in Fig. 2, untilthe cut-away portion of the cam in its travel reaches and then vpassesthe finger 27 when 'the locking bar is permitted to pivot and be forcedin locked position by the spring 39.

The end 16 of the locking bar and its ofi"- set 17 engage with the halflink and abutment just before the work engaging element reaches the endof its down-stroke to act upon the work and continue to be engagedtherewith until the cam engages the finger 27. This operation isrepeated upon each revolution of the driving shaft 1.

If an obstruction, as for instance the finger 41 of the operator, isinterposed or projected between the work engaging element 9 and theanvil 10, which finger is in thickness in excess of an eighth of an inch(or any predetermined thickness) the downward stroke of the head will bearrested and the head and link will idle, the crank pin 3 completing itsstroke by passing or moving, with the bushing 18, through the slot 19,since the end 16 and off-set 17 of the locking bar 13 cannot Contactwith the abutment or shoulder 15, as shown in full lines in Fig. 2,owing to it-s being in a position below shoulder 15 where it cannotengage the shoulder 15 or end of the link 40 and therefore no pressurecan be exerted upon the obstruction. A ball 42 is forced in contact withthe side of the tang 33 of the half link by a spring 43 to provide aslight friction to yieldingly hold the half link and end link in properrelative positions for engaging the locking bar and of-set.

Attention is called to the fact that the locking bar is positively heldin unlocked position by cam action until the working element reaches apredetermined point in its downward stroke, and that the cam can bereadily attached to the end of the driving shaft without changing oraltering the machine in any way and without the use of any appliancesother than the device itself which is self-contained.

It will further be noted that the parts can not be improperly assembledas they must be mounted and held upon the bushing in operative relationto each other preparatory to applying or attaching them to a stayingmachine o1' the like.

Attention is further called to the fact that the off-set 17 is wedgedbetween the end 40 of the half link and the abutment 15 when pressure isexerted upon the element and at the same time the end 16 of the halflink is in contact with the abutment 15 to thus provide a firm footingor point of bearing of locking bar 13 on shoulder 15.

That I claim is:--

1. In a safety device, in combination with a reciprocating work engagingelement, a driving means, means to connect the driving means and workengaging element, a disk mounted on the driving means having a camformed thereon `to maintain said connecting means inoperative, means onsaid cam to' alloW said connecting means to be rendered operative at apredetermined point in its Working stroke When the path of the ele-,ment to the Work yis unobstructed, and means to actuate the connectingmeans to render same operative.

,2. In a safety device, in combination With a A,reciprocating Workengaging element, and an anvil, a driving mechanism, means yto connectsaid Work Vengaging elementto said driving mechanism, a removable `diskconnected tothe driving means .and having a cam to permit thevconnecting means-to be rendered operative at a predetermined point andmeans-to actuate the connecting Ameans to render same operative.

3. .In a ysafety device, `having a `Work vengaging element and meansyfor reciprocating same, a removable disk attached to said means vforreciprocating the Work engaging element and having va cam, and meanscontrolled by the cam Whereby the means for reciprocating the Workengaging element is lrendered inoperative until it reaches a predetermined point in its Working stroke, and is rendered operative afterit vreaches said point. and 'When the path of the elementito the Work isfree.

4;. In a machine having a Work engaging element and anvil, lmeans forreciprocating said element including a link and half link relativelymovable, a lockinobar for locking and unlocking said link andh halflin-k, adisk Vhaving a cam formed thereon attachable to the means forreciprocating the Work engaging element for actuating the locking bar'to unlock the link and half link and for allowing locking of the linkand half link, and meansto actuate the bar into interlocking positionWhen .the path ofthe element to the Work is free.

5. In a machine having a reciprocating Work engaging element and ananvil, a driving means, means comprising a full link and half linkrelatively movable fto connect the drivingmeans and reciprocating Workengaging element, a locking .bar adapted to be locked With and unlockedfromsaid link and half link, means to move said locking bar half linkrelatively movable to connect the driving .means and reciprocating Workengaging element, a locking bar adapted to be locked With and unlockedfrom said link and half link, adisk having a cam .formed thereonattached to said driving means to move the locking ,barffrom alockingpositiommeans to actuate vthe locking lbar to :move same "to lockingpositionWhen the vpath of Atheelement .to the Work is free.

l7. In combination yWith ananvil, a Work engaging element,;and a drivingmeans including an ordinary disk andveccentric pin,

means to connect said Work engaging .element and driving means,meansattachable to both,

8. ,In a safety device for a machine .having a Work 4engaging elementand an anvil, means to reciprocateJ the Work engaging element to exertpressure upon the anvil includinganordinary disk andeccentric pin andmeans attachableto .both the disk and pin Without their modification tothereby iixedly support and position said means to ,render saidreciprocating means linoperative and to prevent same from exertingpressure upon the Work When the Work engagingelement is subjected topressure by van 4obstruction ex traneous to the Work and which is in thepath offtravel of the Work engaging element.

9, In a safety device .for a .machine equipped With a reciprocating Workengaging element and an anvil,driving means for said element, includingan ordinary disk and eccentric pin, means to yconnect said drivingmeansand Work engaging element, 'means attachable to both said disk ,andpin Without their modification, to thereby lfixedly support and.position said means to actuate said connecting means to eXert pressureupon `the anvil and means to render saidv connecting means inoperativeso as to prevent same from exerting pressure When the Work-engagingelement is vsubjected to pressure by an'obstruction in its `path 'oftravel, thicker than the Work.

10. In a safety attachment .for a machine equipped With a reciprocatingWork engaging element and an anvil, a ldriving `means including anordinary disk and eccentric pin, means to connect .said Work engagingelement and drivingl means, means attachable to said disk and pinWithout `their modification and sof .ioo

removable from the driving means Whereby a `reciprocatory Work-engagingelement and an anvil, of driving mechanism, yieldable means connectingthe Work-engaging element and the driving mechanism, and means removablymounted on the driving mechanism for controlling the operation of theyieldable connecting means.

12. In a safety device, in combination with a reciprocatoryWork-engaging element and an anvil, of driving mechanism, yieldable 10means connecting the Work-engaging element In testimony whereof I aiixmy signature 15 in presence of two Witnesses.

CHARLES F. ROOT. Witnesses:

JOHN H. Cose, PEARL M. YUNOHER.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents, Washington, I). C.

